Packing-ring



A. J. MUMMERT.

PACKING RING.

APPLICATION FILED JAN. 10, 1918.-

1,356 ,461, Patented Oct. 19,1920.

W/T/VESSES.

ATTORNEY Arden rfflummerf' the oil scraping edge thereof does not come UNlTED STATES PATENT OFFICE.

ARDEN J. MUMMERT, OF ST. LOUIS, MISSOURI, ASSIGNOR T0'MCQUA. Y-NORRIS MANU- FACTURING COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

PACKING-RING.

Specification of Letters Patent.

Patented Oct. 19, 1920.

Application filed January 10, 1918. Serial No. 211,152.

To all whom it may concern Be it known that I, ARDEN J. MUMMERT a citizen of the United States, residing at St. Louis, State of Missouri, have invented certain new and useful Improvementsin Packing-R-ings, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

The present invention is an improvement on the packing ring forming the subjectmatter of my U. S. Patent No. 1,210.674, bearing date January 2, 1917, and likeit has for its object to provide a piston packing ring for internal combustion engines which shall prevent the lubricating oil distributed over the inner walls of the cylinder from reaching the combustion chamber. A onepiece packing ring in order to bear uniformly against the cylinder walls at all points is usually made eccentric (as shown in my aforesaid patent), that isto say the inner and outer faces of the ring are eccentric to one another, an eccentric ring expanding in such a way as to exert substantially uniform radial pressure against the cylinder walls throughout its entire circumference. A serious objection to the one-piece ring is that it is stiff and fails to conform to the contour of the cylinder walls unless such walls are perfectly circular in cross-section, and the cylinder is straight and true and the ring ground perfectly true and round. In an engine of the character referred to the piston takes the place of the conventional cross-head of the steam engine, the angularity of the connecting rod coupling the piston to the crank-shaft causing the piston to exert a pressure against the inner walls of the cylinder in opposite directions, such pressure in time imparting to the cylinder an elliptical or oval cross-section. In order that the packing ring may gather the oil from the cylinder walls at all points to prevent the lubricant reaching the combustion chamber, it is apparent that the scraping edge of thering must engage the walls throughout the entire circumference of the ring. Since a one-piece ring does not readily adjust itself to an inclosing wall unless such wall be a true cylinder, it follows that in a cylinder which has been worn into oval or elliptical form in cross-section, a one-piece ring can not be used to advantage because in contact with the cylinder walls at all points, a considerable portion of the oil being left free to find its way into the combustion chamber of the engine. To rebore worn cylinders is expensive and in many cases prohibitive. One of the objects sought by my present improvement is to provide an oil scraping ring which will be effective on worn cylinders. To this end resort must necessarily be had to a ring which will readily adjust itself to the cross-sections of the cylinder at all points whether thesame be circular, oval, elliptical, or any other form. Such a ring too, will have the advantage in that it will exert a substantially uniform radial pressure against its inclosing walls, and will -furthermore cause the scraping or cutting edge of its oil collecting basin to reach all portions of the walls over which theoil film is distributed. To attain the objects here sought I provide a packing ring composed of a pluralit of split annular members or bands (usua ly two, as a greater ving oil collecting basin are disposed on the 'outer band, this band ordinarily having a larger area exposed to and in contact with the walls of the cylinder and more body for accommodating an oil basin. The advan tages of the present improvement over the one-piece ring such as shown in my patent aforesaid will be apparent from the following detailed description in connection with the accompanying drawings in which Figure 1 represents a longitudinal section of a gas engine cylinder, with the piston 1n elevation showing one form of my improved ring applied thereto; Fig.2 is an enlarged cross-section of the ring; Fig. 3 isa bottom plan thereof on a reduced scale; Fig. 4 is an edge or-outer face view of the ring; Fig. 5 is a cross-section of a modified form of ring;

Figs. 6 to 15 inclusive are diagrammatic,

' shown as equipped with .two of the imsufficient. I outer annular resilient imperforate, split proved rings, though in practice a single ring positioned at the end of the piston adjacent the combustion chamber is generally The packing ring comprises an band 1, one side of which is provided with an inwardly turned flange 1, said flange engaging the unflanged side f an. inner annular resilient imperforate split band 2 provided with an outwardly turned flange 2' on the opposite side of the ring, said flange 2 engaging the unflanged side of the outer band 1. As well understood in the art, the bands" are usually assembled to bring the split or gap of one band preferably dia-. metrically opposite the split or gap of the other band. The hands when assembled as shown (Fig. 2) constitute a packing ring, being received as well understood in the art in the peripheral groove h of the piston, the

I outer face of the outer band or member 1 and the contiguous face of the flange 2' of the inner band or member 2 engagingthe cylinder walls, that is to say, serving as packing (and lubricating) surfaces in the sense as understood in the art. Disposed along theouter face of the band 1 contiguous to the side thereof facing the crank-case (not shown) or at what corresponds to the outer lower corner of the band is a basin or receptacle a the opposing walls of which are inclined to the axis of the ring and terminate respectively in an upper cuttingor shearing edge e disposed on, the surface of the cylinder defining the bearing or packing surfaces of the assembled bands aforesaid,

, and in a lower edge e disposed on the circumference of a circle interior to the cylinder aforesaid, t at is to say, clearing the inner walls of the cylinder so as to leave an between the side faces). In a packing ring which isthree and one-half inches inside diameter, the width of the ring would be substantially one-quarter of an inch and the thicknessv (between the inner and outer faces) about five thirty-seconds of an inch. In such a ring therefore the thickness of each band (the dimension along the radius ofthe ring) would be substantially five sixty-fourths of an inch, and the. depth of each flange (1, 2',) likewise five sixtyfourths.

The thickness of the respective flanges being one-fourth the width of the' ring, it follows that each flange would be one-sixteenth of an inch thick, leaving the width of the unflanged portion of each band one-eighth of an inch. The section shown in Fig. 2 is enlarged substantially three times over the actual section of a ring having the dimensions above specified. \Vere the ring made of one piece we would have a single mass of metal. with a cross-section of one-quarter inch by five thirty-seconds of an inch provided the ring were of the concentric variety; if eccentric the crosssection would be somewhat larger at the thickest portion of the ring. Being made of two bands, the unflanged portion of each band is reduced to one-half the thickness of the 0ne-piece ring andthereby rendered much more resilient, yielding and pliable, the bands readily conforming to any con-- tour which may be imposed on the inner walls of the cylinder by the action of the piston, due to the angularity of the connecting rod.

It is of course to be understood that the wiping or scraping of the oil from the walls of the cylinder by the cutting edge e of the upper basin wall with each down stroke of the piston does not remove all the lubricant from said walls, but only that excess which but for the wiping, would find its way past the ring into the combustion chamber of the engine. A. film of oil will be permanently left between the ring and cylinder walls for lubricating purposes. A packing ring should however serve not only as an oil or lubricant distributer, but as an effective packing member, that is to say as a member for preventing the leakage or escape of gases from one side of the piston to the oppositeside. To serve effectively in the latter capacity it should present a maximum area of contact to the walls of the cylinder. This area of contact should correspond with the area of the outer face of the ring; and with the ordinary packing ring, such is the case. Then however we impose on the ring the additional function of-a sealing member operating to prevent the free flow of oil past it by providing the ring with an oil basin such .as a with an oil scraping edge e, the removal from the ring of thenecessary metal to form such a basin imparts to the resulting ring a cross-section different from that of the original ring. Thus in Fig. 2, the band 1 before the removal of the metal to form the basin q, was L-shaped in cross-section, the outei bounding lines of the section intelrsecting at the outer corner thereof. The injection of the basin a however destroys this cross-section, converting the said band into a. sealing member, and leaving a differeiif'cross-section to take up the stresses imposed on' the band? The bands being split naturally expand when left free, andwhen inserted into the cylinder are held closed or contracted the walls thereof, the pressure of the bands against the cylinder walls maintaining a tight joint with said. walls. As seen in Fig. 2 the crossse'ction of the packing ring would be a complete rectangle were it not for the basin a in the band 1; and in a one-piece ring having such a cross-section the stresses would be so distributed as not to disturb the parallelism of the inner and outer faces of the ring with the axis thereof. This would likewise be true of a band of a multiple-piece ring having inner and outer parallel faces even in cases where such band was flanged as is the case with the form under consideration. When however we excise from a band such as 1 sufficient metal to form the basin (1, the resulting cross section (when the band is under stress) will suffer a strain or distortion tending to spread apart the opposing walls of the basin and to tilt the outer face of the band out of contact with the cylinder walls and out of parallelism with the axis of the ring, 'so that all the wear comes on the edge e. The band could thus no longer serve its purpose as an effective packing element; neither could it be of service for any length of time under such distortion. The presence of the inner resilient, outwardly expanding band 2 however prevents or arrests this distortion, said band 2 by virtue of its radial pressure maintaining the outer face of the band 1 for the full width thereof in contact with the walls of the cylinder. In order to function in the manner herein described, it is obvious that the initial tension imparted to the restraining band 2 must be greater than that of the outer band 1, or suflicient to overcome the distortionwhich, if not restrained, said outer band would necessarily suffer. In a one-piece ring the distortion referred to is prevented by equipping the ring with two basins a, one on each side of the ring, but since a one-piece ring even with its distortion corrected as here indicated is still open to the objection that it does not readily conform and adjust itself to the cylinder walls unless the cross-section of the latter be a perfect circle at all points (the one-piece ring being of little service in a cylinder made oval or elliptical from wear as previously pointed out) it follows that the ideal packing and sealing ring for cylinders of internal combustion engines is a two-piece ring one of which pieces (or bands) is equipped with an oil collecting basin such as or on the order of that herein described. By equipping one of the bands (preferably the one having the larger surface exnosed to the cylinder walls) with an oil collecting basin as described, a new function is at once imposed on the cooperating band (or bands where more than two bands should be employed), to wit, the function of averting or correcting any distortion due to the stresses imposed on the new cross-section of the oil-sealing band. In the diagrammatic cross-section Fig. 16, the character of distortion referred to is indicated, the full line illustration showing the position the band 1 would assume when relaxed or in the open, and the dotted illustration showing the distortion the same tends to suffer when kept under tension by the walls of the cylinder by which it is held compressed and against which it exerts radial pressure to serve its purpose as a packing. The band 2 as above stated, corrects such distortion.

It is of course obvious that the invention is susceptible of considerable modification. Thus, in Fig. 5 I show a ring composed of an inner resilient imperforate split band'3 provided with an outwardly extending flange 3, the body .of the'band being the full width of the ring. The outer bandJl of this ring has no flange but in other respects its construction is the same as that of the band 1 of the ring first described, being, provided at the lower outer corner with an oil basin a with cutting and clearing edges e, 6, respectively, the edge e being spaced from the cylinder walls by the clearance 03. In this form any distortion suffered by the band 4 is corrected by the band 3. Other forms of the invention are possible. Thus, in F i n 6 we have an outer band 5 with an inwardly directed flange 5, and an inner band 6 with an outwardly directed flange 6 provided with an oil basin a; in Fig. 7 we have an inner band 7 with outwardly directed flange 7 and an outer band 8 with an inwardly directed flange 8, and an oil basin a; in Fig. 8 we have an inner band 9 with an outwardly directed flange 9 and an outer band 10 with an inwardly directed flange 10, and with an oil basin a; in Fig. 9 we have an outer band 11 with an inwardly directed flange 12, and an inner band 13 with an outwardly directed flange 13 provided with an oil basin 0/; in Fig. 10 we have an outer band 1 1 with an inwardly directed flange 14 and an inner band 15 with an outwardly directed flange 15' provided with an oil basin a; in Fig. 11 we have a ring on the order of Fig. 5, said ringcomprising an outer band 16 having an oil basin (1, ,and an inner band 17 with an outwardly directed flange 17' disengaged however from the cylinder walls; in Fig. 12 we have an outer band 18, and an inner band 19 with an outwardly directed flange 19' provided with an oil basin (1'; in Fig;

13 we have an outer band 20 .on the order of that shown in Fig. 12 but differently proportioned, and an inner band 21 with an outwardly directed flange 21 provided with an oil basin a; in Fig. 14 we have an outer band 22 on the order of that shown in Figs. 12 and 13 but differently proportioned, and an inner band 23 with an outwardly directed flange 23' provided with an oil basin a; and in Fig. we have an inner band-24 disengaged from the cylinder walls, and an outer band 25 with an inwardly directed bottom flange 25, and with an oil basin a. Many other forms not illustrated or mentioned are possible as must be obvious to those skilled in the art. With the exception of the forms shown in Figs. 6, 9, 10, 12, the

oil basin is disposed on the band presenting the largest area or rubbing surface to the walls of the cylinder. This is due to the fact that the band presenting the smallest,

1 the flange of the other) present bearing surfaces to the cylinder walls. In Figs. 11 and 15 however only the outer band engages the cylinder walls, the inner band serving merely as a means to correct or prevent the distortion due to the presence of the oil basin in the outer band. Again, while in some of the rings the oil basin is formed in the outer band, in others the basin is in the inner band. In otherwords my invention contemplates the positioning of the oil basin in either the inner or outer band, and in rings in whichone or both (or all where more than two bands should be employed)( bands present bearing Surfaces to the walls of the cylinder.- In all cases the flanges of the respective bands are preferably (though not necessarily) disposed at right angles-to the axes of the rings of which the bands form the component parts, so that the distortion of the sealing band, or the member having the basin is arrested either by a band or member provided with an angle by which the sealing member is received, or by a member received in the angle formed in the sealing member suffering the distortion. Examples of the first type are shown in Figs. 2, 5, 8 and 11, the second type being shown for example in Fig. 15. This construction (or its equivalent) result's in a form of contact between the members which operates to resist in two directions the distortion of the oil-sealing member or band carrying the oil collecting basin. This is apparent from the diagram in Fig. 16 where the inward deflection of the band 1 would be arrested by the band 2, and the upward deflection of the upper side of the band 1 -1 would be resisted by the lower side of the band 2, the latter resisting, as previously described, the inward deflection of the band 1. So here again We have a resistance offered to distortion in two directions. Thus a new function is imposed on the bandor member cooperating with the sealing member of the ring, I do not of course wish to be restricted as tothe number of directions in which the restraining band ofi'ers resistance to distortion of the sealing band. Neither am I to be restricted to a sealing band having the specific cross-section'of oilcollection basin here shown, the invention contemplating broadly the restraining against distortion of any band having an.

oil-collecting basin (or its equivalent) so positioned or constructed as to unbalance the stresses to which the band is subjected when in service.

Having described my invention what I 'claiml is:

1. A packing ring comprising two resilient s l'i-t bands, the one surrounding the other, t e outer band being provided with a peripheral oil-collecting basin at the lower outer corner of the band operating to cause distortion of the band by reason of the unbalanced stresses to which the band is subjected when in service, the inner band enga ing the outer band along its inner face and along the side opposite that adjacent to the basin, and being tensioned to arrest the' distortion in the outer band due to said stresses.

2. A packing ring comprising two flanged resilient split bands, the one surrounding the other, the outer band being provided with a peripheral oil-collecting basin at the lower outer corner of the band adjacent the flange thereof operating to cause distortion of the band by reason of the unbalanced stresses to which the band is subjected when in service, the unflanged side of the inner band engaging the flange of the outer band, and the flange of the'inner band engaging the unfiangedside of the outer band or that opposite from the basin, and the outer face of the inner band engaging the inner face of the outer band, said inner band operating to arrest the distortion in the outer band due to the stresses aforesaid.

3. A packing ring comprising two resilient split bands, the one surrounding the other, the outer band being provided with an oil-collectin basin at the lower outer. corner of the ban operating to cause distortionof the band by reason of the unbalanced stresses to which the band is subjected when in service, the inner band engaging the outer band along its inner face and being tensioned to arrest the distortion in the outer band due to said stresses.

4. A packing ring comprising two resilient split bands, the one surrounding the other, one of the bands being provided with a peripheral oil-collecting basin at the lower outer corner of the band operating to cause distortion of the band by reason of the unbalanced stresses to which the band is subjected when in service, the other band being tensioned, and cooperatively positioned relatively to thevfirst mentioned band, to arrest the distortion in said band due to the stresses aforesaid.

In testimony whereof I affix my signature in presence of two witnesses.

. ARDEN J. MUMMERT. Witnesses:

EMIL STAREK, HARRY A. BEIMES. 

